Combination of mangiferin and T0901317 targeting autophagy promotes cholesterol efflux from macrophage foam cell in atherosclerosis.

BACKGROUND: The synthetic liver X receptor ligand (LXR) T0901317 (T0) has been reported to attenuate atherosclerosis (AS) without hyperglyceridemia due to innovative drug combination or nano-sized drug delivery. Given the key roles of mangiferin (MGF) in lipid metabolism and atherogenesis, it is critical to investigate progression of atherosclerotic lesion after combined treatment of MGF and T0. METHODS: Atherosclerotic plaque formation and hepatic lipid accumulation were compared in Apoe-/- mice among T0 and/or MGF treatment. The in vitro functions of MGF and T0 were analyzed by Oil-red O staining, cholesterol efflux assay, transmission electron microscopy and western blot analyses with or without acetylated low density lipoprotein. RESULTS: The combination therapy are effective regulators for atherosclerotic plaque formation in Apoe-/- mice, due to upregulation of ABCA1 and ABCG1 induced by LXR activation. Subsequently, we identified autophagy promoted by MGF and T0 treatment establishes a positive feedback loop that increases cholesterol efflux, resulted from LXRα activation. Under atherogenic conditions, the autophagy inhibitor CQ abolished the enhancement effect on cholesterol outflow of MGF and T0. Mechanically, MGF and T0 promotes LXRα and mTOR/AMPK signaling cascade in macrophage, and promotes AMPK signaling cascade in hepatocyte, leading to lipid metabolic homeostasis. CONCLUSIONS: Altogether, our findings reveal that MGF and T0 engages in AS therapy without side effects by activating AMPK-dependent autophagy to promote macrophage cholesterol efflux, and MGF might serve as a natural compound to assist T0 in AS via targeting autophagy.

Improvement of LXR-mediated lipid metabolism in nephrotic model kidney accompanied by suppression of inflammation and fibrosis.

Kidney disease affects millions of people worldwide. Chronic kidney diseases, such as diabetic nephropathy, are often accompanied by nephrotic syndrome, which causes a large amount of protein and lipid to leak out into the urine. Leaked lipids are well known to accumulate in the proximal tubules as lipid droplets. However, the role of lipid metabolism in the kidney has not been thoroughly studied, and the relationship between accumulated lipid and pathological progression is often unknown. In this study, we showed that reducing accumulated lipids by exerting an agonistic effect on Liver X receptor, one of the nuclear receptors known to play an important role in lipid metabolism, suppressed the development of pathological conditions, such as inflammation and fibrosis, in a nephrosis model. Until now, many renal disease treatments have focused on suppressing the inflammatory response. However, it is now clear that even if the direct anti-inflammatory response is weak, the spread of inflammation and fibrosis can be suppressed by reducing accumulated lipids. Our results suggest that reducing abnormal lipid accumulation in the kidney could lead to disease treatment.

Liver X receptor agonists exert antitumor effects against hepatocellular carcinoma via inducing REPS2 expression.

Recent studies show that liver X receptor (LXR) agonists exert significant antitumor effects in a variety of tumor cell lines including hepatocellular carcinoma (HCC). But the molecular mechanisms underlying LXR antitumor activity are not fully understood. In this study we investigated the effect of LXR agonist T0901317 (T317) on HCC development and its relationship with RalA binding protein 1 (RALBP1)-associated EPS domain containing 2 (REPS2)/epidermal growth factor receptor (EGFR) signaling axis. We showed that T317 (0.1-0.5 µM) dose-dependently increased REPS2 expression in normal hepatocytes (BNLCL.2 and LO2) and HCC cells (HepG2 and Huh-7). Using promoter activity assay and chromatin immunoprecipitation (CHIP) assay we demonstrated that T317 enhanced REPS2 expression at the transcriptional level via promoting the binding of LXR protein to the LXR-response element (LXRE) in the REPS2 promoter region. We showed that the inhibitory effect of T317 on the proliferation and migration of HCC cells was closely related to REPS2. Moreover, we revealed that T317 (400 nM) increased expression of REPS2 in HepG2 cells, thus inhibiting epidermal growth factor (EGF)-mediated endocytosis of EGFR as well as the downstream activation of AKT/NF-κB, p38MAPK, and ERK1/2 signaling pathways. Clinical data analysis revealed that REPS2 expression levels were inversely correlated with the development of HCC and reduced REPS2 expression associated with poor prognosis, suggesting that REPS2 might be involved in the development of HCC. In conclusion, this study provides new insights into the potential mechanisms of LXR agonist-inhibited HCC.

RORα antagonist T0901317 promotes EMT in human gastric cancer MGC803 cells by RORα/β-catenin signal / 中国药理学通报

Aim To investigate the effect of RORα antagonist T0901317 promoting EMT (epithelial-mesenchymal transition) of human gastric cancer MGC803 cells by RORα/β-catenin signal. Methods Cell proliferation was detected by MTT. Cell migration and invasion were detected by cell scratch and Transwell assay respectively. RORα/β-catenin signaling molecules were detected by Western blot and immunofluorescence. RORα binding to β-catenin protein was detected by immunoprecipitation. Results MTT assay showed that the proliferation ability of T0901317 cells increased in a time-dependent manner compared with MGC803 cells (P < 0. 05). Cell scratches and Transwell experiments showed that the migration and invasion ability of T0901317 cells were significantly enhanced compared with MGC803 cells (P < 0. 05). Western blot analysis showed that RORα protein was significantly down-regulated after T0901317 compared with untreated group (P < 0. 05), and total β-catenin protein and nuclear β-catenin in MGC803 cells were up-regulated after T0901317 (P < 0. 05). Compared with the control group, RORα protein binding to β-catenin protein significantly decreased after T0901317 treatment (P < 0. 05). Compared with MGC803 cells treated with T0901317, the long spindle cells increased and the heteromorphism was more obvious. T0901317 significantly up-regulated the expression of Rac1, TGFβ1 and Vimentin in MGC803 cells (P < 0. 05), and inhibited the expression of E-cadherin (P < 0. 05). Conclusion T0901317 can promote the proliferation, migration, invasion and EMT in human gastric cancer MGC803 cells by RORα/β-catenin signal.

Nanodisc delivery of liver X receptor agonist for the treatment of diabetic nephropathy.

Dyslipidemia is recognized to be an important contributor to the progression of diabetic nephropathy (DN), leading to lipoprotein dysregulation, excessive mesangium expansion as well as inflammation in the glomeruli. Thus, dual targeting of abnormal cholesterol metabolism and inflammatory responses of mesangial cells represents an alternative approach for DN treatment. Herein, we sought to develop a renal-targeting therapeutic strategy for diabetic nephropathy by modifying synthetic high-density lipoprotein (sHDL) nanodiscs with a kidney targeting ligand (KT peptide) and encapsulating a liver X receptor (LXR) agonist in the modified sHDL. LXR agonists delivered by sHDL can facilitate the removal of excessive lipids from mesangial cells, ameliorate inflammation and restore normal renal function. Overall, our data suggests that our optimized KT-targeted sHDL/TO nanodiscs (KT-sHDL/TO) generate potent therapeutic efficacy not only by more efficient cholesterol efflux, but also by suppressing mesangial cell proliferation. Most importantly, in a DN murine model, KT-sHDL/TO ameliorated dyslipidemia and inflammation superior to blank sHDL and non-targeting sHDL/TO formulations, showing promise for future clinical translation in DN treatment.

Design, synthesis and structure-activity relationship of 4-(1,1,1,3,3,3-hexafluoro-2-hydroxyisoprop-2-yl)phenylsilane derivatives as liver X receptor agonists.

Liver X receptor (LXR) α and LXRß are nuclear receptors playing key roles in lipid metabolism, and LXR ligands are attractive drug candidates for metabolic disorders. Here we report the structural development of 4-(1,1,1,3,3,3-hexafluoro-2-hydroxyprop-2-yl)phenylsilane derivatives as LXR agonists bearing silyl functionalities as the hydrophobic pharmacophore, based on the structure of the known sulfonamide LXR agonist T0901317. Most of the synthesized compounds exhibit agonistic activity toward LXRs, but the LXR subtype-selectivity differs depending upon the substituents on the silicon atom. Among them, tri(n-propyl) derivative 12 shows potent LXR-agonistic activity with moderate α subtype-selectivity, while dimethylphenylsilyl derivative 19 shows modest ß-selectivity. These results indicate that silanes can serve as an alternative to the sulfonamide moiety of LXR agonists, and are promising structural options for the development of novel subtype-selective LXR agonists.

LXRß Activation Inhibits the Proliferation of Small-cell Lung Cancer Cells by Depleting Cellular Cholesterol.

BACKGROUND/AIM: Liver X receptors (LXRs) are nuclear receptors with various functions, including the regulation of cholesterol metabolism, glucose homeostasis, and inflammation. We previously reported that LXR activation inhibits the growth of oral cancer cells by inducing cellular cholesterol efflux and that LXRß is expressed mainly in small-cell lung cancer (SCLC) tissues. SCLC is one of the most aggressive cancers, and identifying an effective therapeutic target molecule is desirable. Therefore, we investigated whether LXRß could be an effective target molecule for SCLC treatment through in vitro experiments. MATERIALS AND METHODS: We evaluated the influence of treatment with the LXR agonist T0901317 on cell proliferation and apoptosis in SCLC cell lines using cell viability, BrdU-ELISA, FACS, and western blot analyses. Moreover, the mechanism by which T0901317 inhibits SCLC cell proliferation was elucidated using qRT-PCR, western blot, a cholesterol quantification assay, and a genome editing technique. RESULTS: We showed that cultivated SCLC cells expressed LXRß and that an LXR agonist inhibited the proliferation of SCLC cells without toxicity to normal cells. Furthermore, the antitumoral effect of an LXR agonist on SCLC cells was attributed to the induction of ABCA1 by LXRß activation, resulting in an increase in cellular cholesterol efflux via ABCA1. CONCLUSION: The activation of LXRß up-regulates ABCA1 expression, causing cholesterol depletion in cancer cells. This mechanism could be a novel target strategy for SCLC.

Tritium hydrogen-isotope exchange with electron-poor tertiary benzenesulfonamide moiety; application in late-stage labeling of T0901317.

The multifunctional radioligand [3 H]T0901317 ([3 H]1) has been employed as a powerful autoradiographic tool to target several receptors, such as liver X, farnesoid X, and retinoic acid-related orphan receptor alpha and gamma subtypes at nanomolar concentrations. Although [3 H]1 is commercially available and its synthesis via tritiodebromination has been reported, the market price of this radioligand and the laborious synthesis of corresponding bromo-intermediate potentially preclude its widespread use in biochemical, pharmacological, and pathological studies in research lab settings. We exploit recent reports on hydrogen-isotope exchange (HIE) reactions in tertiary benzenesulfonamides where the sulfonamide represents an ortho-directing group that facilitates CH activation in the presence of homogenous iridium(I) catalysts. Herein, we report a time- and cost-efficient method for the tritium late-stage labeling of compound 1-a remarkably electron-poor substrate owing to the tertiary trifluoroethylsulfonamide moiety. Under a straightforward HIE condition using a commercially available Kerr-type NHC Ir(I) complex, [(cod)Ir (NHC)Cl], the reaction with 1 afforded a specific activity of 10.8 Ci/mmol. Additionally, alternative HIE conditions using the heterogeneous catalyst of Ir-black provided sufficient 0.72 D-enrichment of 1 but unexpectedly failed while repeating with tritium gas.

Targeting macrophage liver X receptors by hydrogel-encapsulated T0901317 reduces atherosclerosis without effect on hepatic lipogenesis.

BACKGROUND AND PURPOSE: Targeting macrophage but not hepatocyte liver X receptors (LXRs) can reduce atherosclerosis without effect on hepatic lipogenesis. In this study, we encapsulated LXR ligands with D-Nap-GFFY to form a nanofibre hydrogel (D-Nap-GFFY-T0901317 or GFFY-T0901317) and determined its effect on atherosclerosis, hepatic lipogenesis and the underlying mechanisms involved. EXPERIMENTAL APPROACH: D-Nap-GFFY-T0901317 was subcutaneously injected to proatherogenic diet-fed apoE-deficient (Apoe-/- ) mice, followed by determination of the development of atherosclerosis, liver steatosis and the involved mechanisms, with comparison of T0901317 oral administration. KEY RESULTS: Subcutaneous injection of D-Nap-GFFY-T0901317 to Apoe-/- mice inhibited atherosclerosis at a comparable level as T0901317 oral administration without effect on hepatic lipogenesis. More importantly, D-Nap-GFFY-T0901317 regressed the advanced lesions. In arterial wall, D-Nap-GFFY-T0901317 reduced macrophage/foam cells, necrotic cores and calcification and increased collagen content. It activated expression of ABCA1/G1 and smooth muscle α-actin, while inhibiting expression of intracellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1). D-Nap-GFFY-T0901317 also reduced serum pro-inflammatory cytokines and facilitated Kupffer cell M2 polarization. Mechanistically, D-Nap-GFFY-T0901317 was selectively taken up by macrophages but not hepatocytes, resulting in activation of macrophage ABCA1/G1 expression, while having no effect on lipogenic genes in hepatocytes. Moreover, the selective uptake of D-Nap-GFFY-T0901317 by macrophages was mainly completed in a scavenger receptor class A-dependent manner. CONCLUSION AND IMPLICATIONS: Our study demonstrates that D-Nap-GFFY-T0901317 reduces atherosclerosis without effect on hepatic lipogenesis by targeting macrophage LXRs selectively, indicating its potential application for atherosclerosis treatment.

Inhibition of notch enhances the anti-atherosclerotic effects of LXR agonists while reducing fatty liver development in ApoE-deficient mice.

Liver X receptor (LXR) activation can achieve satisfactory anti-atherosclerotic activity, but can also lead to the development of fatty liver and hypertriglyceridemia. In contrast, Notch inhibition can suppress both atherosclerosis and the hepatic accumulation of lipids. In the present study, we sought to assess whether combining LXR ligand agonists (T317) with Notch receptor inhibitors (DAPT) would lead to enhanced anti-atherosclerotic activity while overcoming the adverse events associated with LXR ligand agonist therapy. The impact of the combined T317 + DAPT therapeutic regimen on atherosclerosis, fatty liver development, and hypertriglyceridemia was assessed using ApoE deficient (ApoE-/-) mice. The results of this analysis suggested that DAPT was able to improve the anti-atherosclerotic activity of T317 without reducing the stability of lesion plaques while simultaneously reducing blood lipids in treated ApoE-/- mice. This combination T317 + DAPT treatment was also linked with a significant upregulation of ABCA1 and the stimulation of reverse cholesterol transport (RCT), as well as with decreases in the levels of intercellular cell adhesion molecule-1 (ICAM-1) and p-p65, and with altered M1/M2 macrophage proportions within atherosclerotic plaques. Importantly, DAPT was also able to reduce T317-mediated lipid accumulation within the liver owing to its ability to reduce SREBP-1 expression while simultaneously increasing that of Pi-AMPKα and PPARα. Together, our results suggest that administering Notch receptor inhibitors to ApoE-/- mice may be an effective means of enhancing the anti-atherosclerotic activity of LXR ligand agonists while simultaneously limiting associated fatty liver and hypertriglyceridemia development in these animals.

Pharmacokinetics of T0901317 in mouse serum and tissues using a validated UFLC-IT-TOF/MS method.

T0901317, a liver X receptors (LXRs) agonist with high-affinity, is widely used to explore the functions of LXRs in various diseases such as atherosclerosis and Alzheimer's disease. However, there is currently little information available about the pharmacokinetics (PK) behavior of T0901317. Here we established a novel ultrafast liquid chromatography-high resolution mass spectrometry method to quantify the concentration of T0901317 in serum, liver, and brain. The chromatographic separation was attained on a C18 (2.1 × 100 mm, 1.8 µm) column using acetonitrile and 0.1 % of formic acid in water as mobile phase operated in gradient elution mode. The mass detection was carried out using negative ions m/z 479.9809 and 322.0882 for T0901317 and internal standard, respectively. The proposed method was fully validated according to the FDA guidelines, and it generally provides good results in terms of linearity (r2 > 0.99), precision (RSD < 18 % and 12 % for LLOQ and other QC levels, respectively), accuracy (between 92.30 % and 108.16 %), and matrix effect (between 86.56 % and 113.81 %). We then for the first time determined and computed the PK parameters of T0901317 in mouse after intraperitoneal administration of a 20 mg/kg dosage. The peak times (Tmax) in serum, liver, and brain were 1.5, 1.5, and 4 h, respectively, while the half-lives (t1/2) were 4.9, 3.3, and 4.5 h, respectively. Taken together, our results provide a significant choice to study the PK property of T0901317, from which the design of the dosing and sampling protocols of LXRs receptor-antagonist experiments employing T0901317 can also benefit.

Approved LXR agonists exert unspecific effects on pancreatic ß-cell function.

Novel agonists of the nuclear liver-X-receptor (LXR) are designed to treat metabolic disorders or cancer. The rationale to develop these new drugs is based on promising results with established LXR agonist like T0901317 and GW3965. LXRα and LXRß are expressed in ß-cells, and expression is increased by T0901317. The aim of the present study was to evaluate whether effects of these drugs on ß-cell function are specific and reliably linked to LXR activation. T0901317 and GW3965, widely used as specific LXR agonists, show rapid, non-genomic effects on stimulus-secretion coupling of mouse pancreatic ß-cells at low µM concentrations. T0901317 lowered the cytosolic Ca2+ concentration, reduced or completely inhibited action potentials, and decreased insulin secretion. GW3965 exerted similar effects on insulin secretion. T0901317 affected the production of reactive oxygen species and ATP. The involvement of the classical nuclear LXRs in T0901317- and GW3965-mediated effects in ß-cells could be ruled out using LXRα, LXRß and double knockout mice. Our results strongly suggest that LXR agonists, that are considered to be specific for this receptor, interfere with mitochondrial metabolism and metabolism-independent processes in ß-cells. Thus, it is indispensable to test novel LXR agonists accompanying to ongoing clinical trials for acute and chronic effects on cell function in cellular systems and/or animal models lacking classical LXRs.

Development of novel silanol-based human pregnane X receptor (PXR) agonists with improved receptor selectivity.

Pregnane X receptor (PXR) is a ligand-dependent transcription factor that is considered to be a potential therapeutic target for multiple diseases. Herein, we report the development and structure-activity relationship studies of a new series of hPXR agonists. Focusing on our recently developed silanol-sulfonamide scaffold, we developed the potent hPXR agonist 28, which shows good selectivity over hLXRα and ß, hFXR, and hRORα and γ. Examination of the structure-activity relationship suggested a possible strategy to manipulate the selectivity. Docking simulation indicated the presence of an additional binding cavity and polar contacts in the ligand-binding pocket of hPXR. This information should be helpful for the future development of more potent and selective hPXR ligands.

Efatutazone and T0901317 exert synergistically therapeutic effects in acquired gefitinib-resistant lung adenocarcinoma cells.

The development of acquired EGFR-TKI therapeutic resistance is still a serious clinical problem in the management of lung adenocarcinoma. Peroxisome proliferator activated receptor gamma (PPARγ) agonists may exhibit anti-tumor activity by transactivating genes which are closely associated with cell proliferation, apoptosis, and differentiation. However, it remains not clear whether efatutazone has similar roles in lung adenocarcinoma cells of gefitinib resistant such as HCC827-GR and PC9-GR. It has been demonstrated by us that efatutazone prominently increased the mRNA and protein expression of PPARγ, liver X receptor alpha (LXRα),as well as ATP binding cassette subfamily A member 1 (ABCA1). In the presence of GW9662 (a specific antagonist of PPARγ) or GGPP (a specific antagonist of LXRα), efatutazone (40 µmol/L) restored the proliferation of both HCC827-GR and PC9-GR cells and obviously inhibited the increased protein and mRNA expression of PPAR-gamma, LXR-alpha, and ABCA1 induced by efatutazone. LXRα knockdown by siRNA (si-LXRα) significantly promoted the HCC827-GR and PC9-GR cells proliferation, whereas incubation efatutazone with si-LXRα restored the proliferation ability compared with the control group. In addition, combination of efatutazone and LXRα agonist T0901317 showed a synergistic therapeutic effect on lung adenocarcinoma cell proliferation and PPAR gamma, LXR A and ABCA1 protein expression. These results indicate that efatutazone could inhibit the cells proliferation of HCC827-GR and PC9-GR through PPARγ/LXRα/ABCA1 pathway, and synergistic therapeutic effect is achieved when combined with T0901317.

Activation of liver X receptors inhibit LPS-induced inflammatory response in primary bovine mammary epithelial cells.

Liver X Receptors (LXRs) belong to the nuclear receptor superfamily, have been reported that activation of LXRs with synthetic ligands has anti-inflammatory effects in various inflammatory diseases. This study aims at investigating the effects of T0901317 (T0), a synthetic LXRs ligand, on lipopolysaccharide (LPS)-stimulated primary bovine mammary epithelial cells (bMECs). BMECs were stimulated by LPS in the presence or absence of T0. The results showed that treatment with T0 significantly inhibited LPS-induced tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6) expression. LPS-induced NF-κB activation was also suppressed by T0. Furthermore, T0 was found to inhibit the translocation of TLR4 to lipid rafts. T0 could activate ATP-binding cassette transporter A1 (ABCA1) dependent pathway which induced cholesterol efflux from cells and disrupted the formation of lipid rafts. Thus, based on those findings we proposed that LXRs agonist might become a novel therapeutic target for inflammation.

LXR activation increases the expression of GnRH AND αMSH in the rat hypothalamus in vivo.

Liver X receptors (LXR) are important transcription factors involved in the regulation of carbohydrate and lipid metabolism. Recently, we described LXR receptors expression in the hypothalamus but their function in this brain area remains unknown. Here, we evaluated the function of LXR on the expression of factors produced in the hypothalamus in vitro and in vivo by Western blotting and immunocytochemistry. More precisely we studied the expression of GnRH and GHRH, αMSH and NPY in male Sprague-Dawley rats. The effects of two synthetic LXR agonists, T0901317 and GW3965, were first tested in vitro. Hypothalamic explants were treated with either T0901317 or GW3965 (10µM) for 2, 4, 6 and 8h. As a positive control the cholesterol ABCA1 and glucose GLUT2 transporters were used. No changes were observed in the expression of the factors evaluated in vitro. The effects of the LXR agonists were then tested in vivo. Rats were injected ICV into the third ventricle with either T0901317 or GW3965 (2.5µg/5µL ICV) and after 3.5h or 24h the hypothalami were dissected out and rapidly frozen for analysis. αMSH and GnRH expression was significantly increased after 3.5h of T0901317 treatment. Anterior/posterior hypothalamic ratio increases for αMSH expression and decreases for GnRH expression after 24h of LXR activation. Altogether these results show that LXR activation affects the expression of GnRH and αMSH, suggesting that LXR in the hypothalamus is capable of modulating hypothalamic responses related to appetite, sexual behavior and reproductive functions.

Effect and mechanism of liver X receptor agonist T0901317 on angiogenesis phenotype of liver cancer / 中华消化外科杂志

Objective To explore the effect and mechanism of liver X receptor agonist T0901317 on angiogenesis phenotype of liver cancer.Methods The experimental study was conducted.Hepatocellular carcinoma MHCC97-H and Huh7 cells and human umbilical vein endothelial cells (HUVEC) were cultured in vitro.Each cell line was divided into 3 groups:control group (non-treated),low concentration group (treated using 1 μmot/L T0901317) and high concentration group (treated using 3 μmol/L T0901317).Cell proliferation was counted with a CCK-8 assay.Quantitative real-time polymerase chain reaction (PCR) was applied to confirm the relative mRNA expression of fatty acid synthetase (FAS) of liver X receptor target genes in 3 groups.Subcutaneous xenograft tumor volume and body mass were measured in MHCC97-H nude mice model.Then mice were sacrificed and tumor tissues were analyzed for CD31 relative expression by immunohistochemistry (IHC) staining.Migration and vessel angiogenesis of HUVEC were determined by Transwell method.Observation indicators:(1) effects of T0901317 on MHCC97-H,Huh7 and HUVEC cells proliferation,(2) effects of T0901317 on liver X receptor with MHCC97-H,Huh7 and HUVEC cells,(3) effects of T0901317 on subcutaneous xenograft tumor growth in MHCC97-H nude mice model,(4) effects of T0901317 on CD31 relative expression in subcutaneous xenograft tumor tissues of MHCC97-H nude mice model,(5) effects of T0901317 on migration of HUVEC,(6) effects of T0901317 on vessel angiogenesis of HUVEC.Measurement data with normal distribution were represented as x±s,and comparisons between groups were analyzed by the t test.Results (1)Effects of T0901317 on MHCC97-H,Huh7 and HUVEC cells proliferation:results of CCK-8 assay showed that percentage of living cells was respectively 100.0％± 1.7％,101.0％±0.7％ and 104.6％± 1.9％ in MHCC97-H control,low concentration and high concentration groups,with no statistically significant difference (F =2.632,P＞0.05).Percentage of living cells was respectively 100.0％ ± 2.7％,97.6％ ± 2.4％ and 103.7％ ± 2.8％ in Huh7 control,low concentration and high concentration groups,with no statistically significant difference (F =1.404,P＞0.05).Percentage of living cells was respectively 100.0％ ±0.7％,100.7％± 1.2％ and 101.3％ ±0.8％ in HUVEC control,low concentration and high concentration groups,with no statistically significant difference (F=0.471,P＞0.05).(2) Effects of T0901317 on liver X receptor with MHCC97-H,Huh7 and HUVEC cells:results of quantitative real-time PCR showed that relative mRNA expressions of FAS in MHCC97-H control,low concentration and high concentration groups were respectively 100.0 ％±2.2％,658.5％±7.7％ and 1 241.0％± 106.8％,with a statistically significant difference among groups (F=46.227,P＜0.05),and with a statistically significant difference between MHCC97-H control group and MHCC97-H low concentration and high concentration groups (t =70.025,8.274,P ＜ 0.05) and between MHCC97-H low concentration and high concentration groups (t =4.222,P ＜ 0.05).Relative mRNA expressions of FAS in Huh7 control,low concentration and high concentration groups were respectively 100.0％ ± 15.8％,1 225.0％ ± 26.7 ％ and 2 015.0％ ± 215.1％,with a statistically significant difference among groups (F =49.402,P＜ 0.05),and with a statistically significant difference between Huh7 control group and Huh7 low concentration and high concentration groups (t=39.460,8.879,P＜0.05) and between Huh7 low concentration and high concentration groups (t =2.836,P ＜ 0.05).Relative mRNA expressions of FAS in HUVEC control,low concentration and high concentration groups were respectively 100.0％ ± 19.6％,790.8％ ± 116.5％ and 1 756.0％ ± 55.0％,with a statistically significant difference among groups (F=185.395,P＜0.05),and with a statistically significant difference between HUVEC control group and HUVEC low concentration and high concentration groups (t =7.639,34.375,P＜0.05) and between HUVEC low concentration and high concentration groups (t =7.488,P＜0.05).(3) Effects of T0901317 on subcutaneous xenograft tumor growth in MHCC97-H nude mice model:results of assay showed that subcutaneous xenograft tumor volume in MHCC97-H control group and MHCC97-H T0901317 group were respectively (935±72)mm3 and (552 ± 47)mm3,with a statistically significant difference between groups (t=4.449,P＜0.05).Body masses of nude mice model in MHCC97-H control group and MHCC97-H T0901317 group were respectively (23.8±0.8) g and (21.7± 1.7) g,with no statistically significant difference between groups (t =1.059,P＞0.05).(4) Effects of T0901317 on CD31 relative expression in subcutaneous xenograft tumor tissues of MHCC97-H nude mice model:results of IHC staining showed that CD31 relative expression in subcutaneous xenograft tumor tissues of MHCC97-H nude mice model was 100％±11％ and 35％±7％ in MHCC97-H control group and MHCC97-H T0901317 group,with a statistically significant difference between groups (t =4.919,P＜0.05).(5) Effects of T0901317 on migration of HUVEC:results of Transwell method showed that percentages of membrane cells in HUVEC control,low concentration and high concentration groups were respectively 100.0％±4.0％,57.3％±1.5％ and 32.7％± 1.7％,with a statistically significant difference among groups (F=163.944,P＜0.05),and with statistically significant differences between HUVEC control group and HUVEC low concentration and high concentration groups (t =9.998,15.434,P＜0.05) and between HUVEC low concentration and high concentration groups (t =10.801,P ＜ 0.05).(6) Effects of T0901317 on vessel angiogenesis of HUVEC:results of vessel angiogenesis assay showed that length of vessel angiogenesis in HUVEC control,low concentration and high concentration groups were respectively 100.0％±3.4％,68.4％ ±3.5％ and 44.7％± 0.5％,with a statistically significant difference among groups (F =38.964,P ＜ 0.05),and with statistically significant differences between HUVEC control group and HUVEC low concentration and high concentration groups (t=6.268,9.831,P＜0.05) and between HUVEC low concentration and high concentration groups (t =3.460,P＜0.05).Conclusion Liver X receptor agonist T0901317 can inhibit vessel angiogenesis of liver cancer.

Systems Pharmacology Dissection of Cholesterol Regulation Reveals Determinants of Large Pharmacodynamic Variability between Cell Lines.

In individuals, heterogeneous drug-response phenotypes result from a complex interplay of dose, drug specificity, genetic background, and environmental factors, thus challenging our understanding of the underlying processes and optimal use of drugs in the clinical setting. Here, we use mass-spectrometry-based quantification of molecular response phenotypes and logic modeling to explain drug-response differences in a panel of cell lines. We apply this approach to cellular cholesterol regulation, a biological process with high clinical relevance. From the quantified molecular phenotypes elicited by various targeted pharmacologic or genetic treatments, we generated cell-line-specific models that quantified the processes beneath the idiotypic intracellular drug responses. The models revealed that, in addition to drug uptake and metabolism, further cellular processes displayed significant pharmacodynamic response variability between the cell lines, resulting in cell-line-specific drug-response phenotypes. This study demonstrates the importance of integrating different types of quantitative systems-level molecular measurements with modeling to understand the effect of pharmacological perturbations on complex biological processes.

Activation of liver X receptor suppresses angiogenesis via induction of ApoD.

Liver X receptors (LXRs) are important sensors and regulators for cholesterol, fatty acid, and glucose. LXRs play essential roles in the development and progression of cardiovascular diseases. We examined the effects of T0901317, a potent LXR agonist, on angiogenesis of human umbilical vein endothelial cells (HUVECs). Treatment with T0901317 inhibited the tube formation and migration of HUVECs and reduced the in vivo angiogenesis, as determined by chorioallantoic membrane assay. T0901317 stimulated gene and protein expression of LXR target gene apolipoprotein D (ApoD). Overexpression of ApoD suppressed the tube formation of HUVECs. ApoD interacted with scavenger receptor class B member 1 (SR-B1), while knockdown of SR-B1 blocked suppressive effects of T0901317 on HUVEC migration. T0901317 treatment or overexpression of ApoD lessened expression of proteins regulating angiogenesis, including phospho-eNOS S1177, phospho-Akt T308, phospho-Akt S473, eNOS, mammalian target of rapamycin, VEGF-A, VEGF-C, IL-8, RhoB, matrix metalloproteinase (MMP)-8, -9, and monocyte chemoattractant protein 1. Our study suggested that activation of LXR interferes with angiogenesis through induction of LXR target gene ApoD, which in turn suppresses PI3K-Akt-eNOS signaling, an essential pathway regulating angiogenesis. ApoD may be a potential therapeutic target for tumor angiogenesis.-Lai, C.-J., Cheng, H.-C., Lin, C.-Y., Huang, S.-H., Chen, T.-H., Chung, C.-J., Chang, C.-H., Wang, H.-D., Chuu, C.-P. Activation of liver X receptor suppresses angiogenesis via induction of ApoD.

B-13 progenitor-derived hepatocytes (B-13/H cells) model lipid dysregulation in response to drugs and chemicals.

Lipid dysregulation is a common hepatic adverse outcome after exposure to toxic drugs and chemicals. A donor-free rat hepatocyte-like (B-13/H) cell was therefore examined as an in vitro model for investigating mechanisms. The B-13/H cell irreversibly accumulated triglycerides (steatosis) in a time- and dose-dependent manner when exposed to fatty acids, an effect that was potentiated by the combined addition of hyperglycaemic levels of glucose and insulin. B-13/H cells also expressed the LXR nuclear receptors and exposure to their activators - T0901317 or GW3965 - induced luciferase expression from a transfected LXR-regulated reporter gene construct and steatosis in a dose-dependent manner with T0901317. Exposing B-13/H cells to a variety of cationic amphiphilic drugs - but not other hepatotoxins - also resulted in a time- and dose-dependent accumulation of phospholipids (phospholipidosis), an effect that was reduced by over-expression of lysosomal phospholipase A2. Through application of this model, hepatotoxin methapyrilene exposure was shown to induce phospholipidosis in both B-13 and B-13/H cells in a time- and dose-dependent manner. However, methapyrilene was only toxic to B-13/H cells and inhibitors of hepatotoxicity enhanced phospholipidosis, suggesting phospholipidosis is not a pathway in toxicity for this withdrawn drug. In contrast, pre-existing steatosis had minimal effect on methapyrilene hepatotoxicity in B-13/H cells. These data demonstrate that the donor free B-13 cell system for generating hepatocyte-like cells may be employed in studies of fatty acid- and LXR activator-induced steatosis and phospholipidosis and in the dissection of pathways leading to adverse outcomes such as hepatotoxicity.